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41.
Strangulation in child abuse: CT diagnosis 总被引:2,自引:0,他引:2
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients. 相似文献
42.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
43.
A retrospective study was performed to estimate the frequency of alloimmunization against red cell (RBC) antigens in a multiply transfused group. Patients (n = 186) were studied who had received at least six blood transfusions during a period of at least 3 months. Some 6944 units of blood were transfused. One hundred forty patients had hematologic disorders. The patients' sera were investigated every 3 months with indirect antiglobulin tests and enzyme-treated RBCs. Twenty-two patients (11.8%) made 33 antibodies. Seven patients made more than one antibody. Eight of the 22 patients (36.4%) made their first antibody before or at the 10th transfusion. The risk of immunization increased with the number of transfusions. Influence of gender and age was not demonstrable. Nor was a relationship demonstrated between blood transfusion reactions and RBC antibody formation; no delayed hemolytic transfusion reactions occurred. Anti-E was demonstrated in 12 patients and anti-K in 15. When the gene frequencies were taken into account, it appeared that anti-E was made by 11.5 percent of E-negative patients, most of whom were immunized after an estimated three transfusions with E-positive blood. Anti-K was made by 8.7 percent of the K-negative patients, after an estimated 2.1 units of K-positive blood. It might be desirable to match red cell units for the E and K antigens in patients at relatively high risk. These are primarily patients who have already formed an antibody and are going to receive many transfusions and women of childbearing age who are to receive more than 4 units of blood. 相似文献
44.
45.
Hypogonadism is a clinical and biochemical syndrome associated with a range of disease states that has significant effects
on morbidity and mortality and also affects quality of life. Because of the increase in life expectancy and prostate carcinoma
(PCa) survival, a significant increase in the number of men with hypogonadism who have undergone presumably curative treatment
of PCa is anticipated. Despite the widespread belief regarding contraindication of testosterone administration to men with
known or suspected PCa, there is no convincing evidence that the normalization of testosterone serum levels in men with low
levels presents a deleterious effect on the evolution of the disease. In the few available case series describing testosterone
replacement therapy (TRT) after treatment of PCa, no case of clinical or biochemical progression was observed. The available
data suggest that TRT can be cautiously considered in selected hypogonadal men previously treated for curative intent of low-risk
PCa and without evidence of active disease. 相似文献
46.
The NADPH-dependent reduction of chromium (VI), a known carcinogen, by
hepatic microsomes was very similar for all five humans examined, with an
apparent Km for chromate of 1.04-1.68 microM, and a Vmax of 10.4- 10.7
nmol/min/mg protein. Inhibitor studies indicate no role for cytochrome
P450s, but a prominent role for flavoproteins, which could include P450
reductase, flavin-containing mono-oxygenase and cytochrome b5. Relative to
anaerobic conditions, Cr(VI) reduction was inhibited only 26-37% by room
air, which indicates that human microsomal Cr(VI) reduction could still
proceed at significant rates, even in tissues with high O2 tensions.
Studies with lung microsomes from one human exhibited Vmax and Km values
that were two-thirds lower and 2.8-fold greater, respectively, than those
of hepatic microsomes from the same individual; other Cr(VI)-reducing
parameters were similar for lung and liver. Various forms of exogenous
iron, when present at 0.76-6.3 microM, markedly enhanced both liver and
lung microsomal rates and Vmax of Cr(VI) reduction, but did not
significantly alter the other Cr(VI)- reducing parameters (Km, effects of
O2 and inhibitors). These iron levels were 3.1- to 26-fold lower than the
initial Cr(VI) concentration, which suggests that iron is serving a
catalytic role. The ratio of human microsomal Cr(VI) reduction rates under
aerobic versus anaerobic conditions remained fairly constant, regardless of
iron concentration. Small increases in intracellular iron could therefore
lead to large increases in the rate and extent of microsomal Cr(VI)
reduction. Individuals that are simultaneously exposed to Cr(VI) and to
agents that increase intracellular iron could therefore be at potentially
greater risk for Cr(VI) toxicity and carcinogenicity.
相似文献
47.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
48.
The UniScept API system was evaluated for agreement of visual versus automated readings of both its identification panels and its antimicrobial susceptibility panels. The biochemical responses of 340 oxidase-negative and oxidase-positive fermentative bacterial cultures were read both visually and automatically in the UniScept API 20E system. Automated and visual readings agreed with 99.3% of the biochemicals. Of the 45 tests that disagreed, the tests for indole and citrate were most often in disagreement. A total of 470 fermentative and nonfermentative cultures were used in the UniScept MIC system to compare visual and automated readings of susceptibility results with 17 antimicrobial agents. Agreement within +/- 1 dilution occurred with 94.1% of the enteric fermenters and with 91.7% of the other cultures. Comparison of visual and automated readings resulted in very major discrepancies in 0.95% of the readings, with the largest percentage of discrepancies associated with glucose nonfermenters (1.8%). It was felt that an automated reading is an acceptable alternative to a visual reading of the biochemicals but that 0.95% was just within the acceptable range of the 1% allowable very major discrepancies in the automated reading of susceptibilities. 相似文献
49.
TEELUCKSINGH S; STEER CR; THOMPSON CJ; SECKL JR; DOUGLAS NJ; EDWARDS CRW 《QJM : monthly journal of the Association of Physicians》1991,78(2):185-190
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene. 相似文献
50.
CR Valeri G Ragno LE Pivacek R Srey JR Hess LE Lippert F Mettille R Fahie EM O''Neill IO Szymanski 《Transfusion》2002,42(12):1618-1618